[linux-lvm] LVM2 full disk & Grub

[linux-lvm] LVM2 full disk & Grub

[Ling Li]

When I was going to install a full-disk LVM2 PV on my hard disk (not for 
the root partition) with grub installed, I had very bad experience. I 
searched the internet for possible warnings. All I got were 1. LVM1 was 
known to be "unfriendly" to boot loader when the full disk is created as 
one PV. and 2. LVM2 solves this problem by allowing the label sector to 
be any of the first 4 sectors in the disk.

However, grub needs more than 3 sectors (in my system, 16 sectors), 
which still conflicts with LVM2 when the full disk is used. So if you 
happen to want to use LVM2 and grub in the same disk, you have to create 
some partitions... NOT the full disk.

I don't know why I couldn't find this kind of information on the 
internet or grub manual or LVM howto. In case there are also other users 
as "careless" as me, my this post might be useful.

By the way, is there an LVM2 howto available somewhere?

--Ling

Re: [linux-lvm] LVM2 full disk & Grub

[Alasdair G Kergon]

On Thu, Feb 12, 2004 at 03:27:48PM -0800, Ling Li wrote:
> However, grub needs more than 3 sectors (in my system, 16 sectors), 

The number 4 is a compile time parameter - you could make it bigger if
you wanted to.

  lib/label/label.h:   #define LABEL_SCAN_SECTORS 4L

I wonder if it's sensible to add an offset parameter, so it skips the
first X sectors, or if it could recognise grub.

> By the way, is there an LVM2 howto available somewhere?
Not yet.  But we've just started to update the existing HOWTO to
cater for LVM2.
 
Alasdair
-- 
agk@redhat.com

Re: [linux-lvm] LVM2 full disk & Grub

[AJ Lewis]

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On Thu, Feb 12, 2004 at 03:27:48PM -0800, Ling Li wrote:
> By the way, is there an LVM2 howto available somewhere?

Work is in progress to add lvm2 information into the LVM HOWTO.  I hope to
have it published in the next few days.  If you have anything that you feel
should really be in it (such as this grub issue) let me know.

Thanks,
-- 
AJ Lewis                                   Voice:  612-638-0500
Red Hat Inc.                               E-Mail: alewis@redhat.com
720 Washington Ave. SE, Suite 200
Minneapolis, MN 55414

Current GPG fingerprint = FE77 4B43 6A9B F982 A731  02FA 2BF5 7574 294A AA5A
Grab the key at: http://people.redhat.com/alewis/gpg.html or one of the
many keyservers out there...
-----Begin Obligatory Humorous Quote----------------------------------------
geep!
-----End Obligatory Humorous Quote------------------------------------------

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[linux-lvm] 答复: [linux-lvm] LVM2 full disk & Grub

[Lu Jian]

Hi,

Could you please tell how can I get the draft HowTo of LVM2?
Thanks

Regards. 

-Lu, Jian 



> -----�ʼ�ԭ��-----
> ������: linux-lvm-admin@redhat.com 
> [mailto:linux-lvm-admin@redhat.com] ���� AJ Lewis
> ����ʱ��: 2004��2��13�� 7:31
> �ռ���: linux-lvm@redhat.com
> ����: Re: [linux-lvm] LVM2 full disk & Grub
> 
> 
> On Thu, Feb 12, 2004 at 03:27:48PM -0800, Ling Li wrote:
> > By the way, is there an LVM2 howto available somewhere?
> 
> Work is in progress to add lvm2 information into the LVM 
> HOWTO.  I hope to have it published in the next few days.  If 
> you have anything that you feel should really be in it (such 
> as this grub issue) let me know.
> 
> Thanks,
> -- 
> AJ Lewis                                   Voice:  612-638-0500
> Red Hat Inc.                               E-Mail: alewis@redhat.com
> 720 Washington Ave. SE, Suite 200
> Minneapolis, MN 55414
> 
> Current GPG fingerprint = FE77 4B43 6A9B F982 A731  02FA 2BF5 
> 7574 294A AA5A Grab the key at: 
> http://people.redhat.com/alewis/gpg.html or one of the many 
> keyservers out there... -----Begin Obligatory Humorous 
> Quote----------------------------------------
> geep!
> -----End Obligatory Humorous 
> Quote------------------------------------------
> 

Re: [linux-lvm] LVM2 full disk & Grub

[Ling Li]

AJ Lewis wrote:
> Work is in progress to add lvm2 information into the LVM HOWTO.  I hope to
> have it published in the next few days.  If you have anything that you feel

Cool! Thanks for your work. A new comer like me really needs such an 
updated manual (though the one for LVM1 is still very useful).

> should really be in it (such as this grub issue) let me know.

Sure, I will if I have more.

--Ling